It sounds like a psychological horror to me. If it can see you, the deep can see you. If it can hear you, the deep can hear. This is very scary and creepy. I wonder how a boy feels after hearing something like this. Now when he knows what his dad does, how is he going to deal with it? Obviously he can't talk to anyone about it as he doesn't want to hurt his dad. His dad said he does it to protect the family. What a situation for this boy! Now I understand the first sentence: All children, even happy ones, are alone.

Are you going to write a continuation story? I don't know but it seems like an open end to me?

I like how you grabbed the idea that you had and how you wrote the story gaining something dark and scary with every single sentence.

Thank you for sharing!